B-po02-038 initial real world operation of a leadless ventricular pacemaker providing atrioventricular synchronous pacing

Recent advances in leadless pacemaker technology have enabled accelerometer based atrioventricular synchronous (AVS) pacing by sensing atrial mechanical contraction (A4 signal). However, real world operation of these devices in clinical practice has not been assessed. To assess programming and longevity in leadless AVS pacemakers in nationwide practice. A retrospective analysis was performed using Micra AV transmissions from the Medtronic CareLink database. Patients with transmissions ≥180 days post-implant were included. Device programming, pacing parameters, and projected battery longevity were summarized based on first qualifying transmission. Among 417 patients, 89%, 1.4%, and 9.6% of patients were programmed to VDD, VDI, and VVI pacing modes. Mean pacing threshold was 0.57 ± 0.35 V. For the 377 patients programmed to VDD/VDI mode, mean A4 amplitude was 2.3 ± 1.8 m/s2 (IQR: 1.70 - 5.1 m/s2). The average change in A4 amplitude from baseline (week 5) to 6 months was -0.18 ± 1.20 m/s2 (P=0.021; n=273). In patients with %VP >90% (n=143), the median %AM-VP (the percentage of ventricular beats preceded by a detected atrial mechanical event) was 75.7% (IQR: 63.4% - 85.3%). For the full cohort, median %VP was 70.6% and median projected battery longevity was 10.8 years with 68.6% of patients having battery longevity ≥10 years (Figure). In this real world analysis of Micra AV patients, A4 amplitude remained stable with minimal changes during follow-up. Median %AM-VP, a correlate of AVS, was 76% comparable to what was seen in clinical trials. The projected battery longevity of patients implanted with Micra AV exceeds 10 years.